// Copyright (c) Microsoft Corporation
// All rights reserved.
//
// MIT License
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
// documentation files (the "Software"), to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and
// to permit persons to whom the Software is furnished to do so, subject to the following conditions:
// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED *AS IS*, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
// BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

// module dependencies
const marked = require('marked');
const URL = require('url').URL;

const baseUrl = 'https://github.com/Microsoft/pai/tree/master/docs/';

const renderer = new marked.Renderer();

renderer.link = (href, title, text) => {
  if (marked.options.sanitize) {
    try {
      const prot = decodeURIComponent(unescape(href))
        .replace(/[^\w:]/g, '')
        .toLowerCase();
      if (
        prot.indexOf('javascript:') === 0 ||
        prot.indexOf('vbscript:') === 0 ||
        prot.indexOf('data:') === 0
      ) {
        return '';
      }
    } catch (e) {
      return '';
    }
  }
  if (href === text && title == null) {
    return href;
  }
  if (href[0] !== '#') {
    href = new URL(href, baseUrl).href;
  }
  let out = '<a href="' + href + '"';
  if (title) {
    out += ' title="' + title + '"';
  }
  out += '>' + text + '</a>';
  return out;
};

module.exports = { renderer };
